The present invention relates generally to a magnetic recording/reproducing apparatus for recording or reproducing information with a magnetic tape being wrapped around a guide drum.
Recently, improvement for current home-use video tape recorders (VTR) is being made for further size-reduction purpose without changing the recording pattern on a magnetic tape. One approach to size-reduction of VTRs is disclosed in the U.S. Pat. No. 4,614,985 issued to the same assignee in which a magnetic tape is wrapped around a guide drum ranged about 270-degrees rather than about 180-degrees for the current VTRs and four video heads are provided at an angular distance of 90-degrees from each other to reduce the diameter of the guide drum to two-thirds of that of the current VTRs.
For keeping the tape interchangeability with the current VTRs it is required that the standard track patterns of video signals to be recorded on the magnetic tape are kept identical, and further the length of magnetic tape in the tape path from the guide drum to the audio control signal head (A/C head) is kept to the standard length of the current VTRs for proper operation of their head tracking servo control.
An example of a tape loading mechanism for a magnetic recording/reproducing apparatus showing the above approach for improvement is disclosed in the U.S. Pat. No. 4,626,938 which is assigned to the assignee of the present application and wherein the diameter of a guide drum is reduced and a magnetic tape is wrapped symmetrically around the guide drum keeping the standard length as well as the standard track patterns. The magnetic recording/reproducing apparatus is arranged such that a guide drum is disposed to be close to a tape cassette to be mounted therein for size-reduction purpose. However, in such an apparatus, loading poles such as vertical and inclined loading poles disposed on a pole base with a predetermined spacing are arranged to be moved from the initial stop position to the loading-terminated position keeping the space therebetween in the radial direction of the guide drum during tape loading. This arrangement takes up a dead space at the peripheral region of the guide drum, thereby causing difficulty of further size-reduction. In addition thereto, there is a possibility of tape damage due to the involvement of the inclined poles during tape loading as discussed later and hence difficulty is imposed to meet the requirements for size-reduction.